Author,Title,Journal,ISSN,Publisher,Date,Volume,Number,Page,URL,URL(DOI) NAKAYA Tomoki,On Spatial Unit Aggregation Problems in the Spatial Interaction Model,"Geographical Review of Japa,. Ser. A, Chirigaku Hyoron",00167444,The Association of Japanese Geographers,1995,68,2,71-92,https://cir.nii.ac.jp/crid/1390282680401183616,https://doi.org/10.4157/grj1984a.68.2_71